1. Field of the Invention
The invention relates to new organosilicon compounds. It furthermore relates to preparations for treating fibers which contain these new compounds, the preparations being particularly suitable for synthetic fibers obtained from the melt and especially polyester fibers.
2. Description of the Prior Art
Polydimethylsiloxanes are used in spinning mills for finishing melt-spun fibers. This use is possible due to the fact that polydimethylsiloxanes, which are generally referred to herein as silicone oils, impart to the treated fibers a low coefficient of friction which varies little with temperature, even at high take-off speeds. In addition, silicone oils are exceptionally heat stable and have a low viscosity-temperature coefficient.
Finishing of melt-spun yarns immediately after they are produced, enables the subsequent drawing and texturing processes to be carried out. Thus, the finish must be a lubricant as well as an antistat. In thermofixing processes carried out on the yarn, components of the finish are cast onto the heating units where they are subjected to long periods of thermal stress. For this reason, the finish must be thermally stable. It is important that the finish cast on the heating unit not gel, yellow or evaporate; the most important requirement being the resistance to gelling. At the same time, the components of the finish should be compatible with one another. This compatibility is especially a problem in considering the compatibility of the polar, surface-active components, which are primarily responsible for the antistatic activity, with the nonpolar methylsilicone oils which are primarily responsible for the lubricating properties.
The compatibility of methylsilicone oils can be improved by partially replacing the methyl groups with alkyl groups of longer chain length. However, the resulting oils no longer possess sufficient thermal stability. Also, the viscosity-temperature coefficient of such modified methylsilicone oils increases greatly.
The partial replacement of methyl groups with phenyl groups also leads to products of a higher viscosity-temperature coefficient, whose lubricating properties are consequently diminished.
German Pat. No. 26 45 459 discloses textile fiber finishes containing as active components:
1 to 99 weight percent of compounds having the formula ##STR4## in which R.sup.1 is a mono-, di- or trialkylphenyl radical, in which the sum of the carbon atoms linked in the form of alkyl radicals is at least 6, and at most 12 per phenyl radical, and/or a trimethylsilyl radical; PA0 99 to 1 weight percent of known conventional finish components. PA0 and/or a trimethylsilyl radical, PA0 R.sup.2 is a methyl radical, PA0 n has a value of 2.5 to 12.5, PA0 0 to 80% of the R.sup.1 radicals are ##STR12## in which R.sup.3 is an alkyl radical with 1 to 16 carbon atoms, an organoacyl radical with 1 to 12 carbon atoms or an aryl radical, PA0 n=3 to 30. PA0 5 to 100 weight percent of the inventively modified silicone oils of Group A, PA0 0 to 90 weight percent of nonpolar or weakly polar oils of Group B, PA0 0 to 30 weight percent of nonionic compounds of Group C, PA0 0 to 15 weight percent of ionic surfactants of Group D, and optionally conventional additives,
R.sup.2 is an alkyl radical with 1 to 6 carbon atoms, in which the carbon chain can be interrupted by the ##STR5## and/or the M.sub.a --O--R.sup.3 radical, in which R.sup.3 is a mono-, di- or trialkylphenyl radical, the sum of the carbon atoms linked in the form of alkyl radicals being at least 6, and at most 12 per phenyl radical, and/or the ##STR6## radical; R.sup.4 is an alkyl radical with 1 to 16 carbon atoms and/or ##STR7## in which M is an alkylene radical with 1 to 3 carbon atoms, PA1 and the average molecule contains 5 to 30 Si atoms of which no more than 20 mole percent are Si* atoms; and 0.5 to 10 mono-, di- or trialkylphenyl radicals, and PA1 b has a value of 0 to 2 and PA1 c has a value of 1 to 30, PA1 a=1 to 2; and PA1 b=1 to 2, PA1 c=1 l to 30, and PA1 r=8 to 12, PA1 n=preferably 5 to 10.
n has a value of 2.5 to 15, PA2 m has a value of 0 to 5, and PA2 a has a value of 0 or 1,
These compounds possess high thermal stability and fibers treated with such finishes show excellent frictional properties.
These compounds are related to the compounds of German Pat. No. 26 45 890 having the formula ##STR8## in which R.sup.1 is a mono-, di- or trialkylphenyl radical, the sum of the alkyl carbon atoms per phenyl radical is 6 to 12, and/or the ##STR9## radical, in which R.sup.3 is an alkyl radical with 1 to 16 carbon atoms, and an organoacyl radical with 1 to 12 carbon atoms or an aryl radical,
and the average molecule contains 5 to 25 Si atoms and 0.4 to 2.0 mono-, di- or trialkylphenyl radicals, which are linked over Si--O--C bonds directly to Si atoms, and 0.4 to 2.0 polyether blocks.
Melt spin finishes which contain such compounds exhibit improved compatability between the organosilicon compounds and the oils and surfactants, which are usually contained in melt spin finishes. This improved compatability is attributable to the presence of oxyalkylene units in the organosilicon compounds which, however, decreases the thermal stability of the melt spin finishes as compared to that of the compounds of German Pat. No. 26 45 459. It is therefore necessary for each particular application to find the optimum balance between the alkyloxy and oxyalkylene. Therefore, the compounds of German Pat. No. 26 45 890 are used advantageously when a high compatibility with the other additives of the melt spin finish is required and the thermal stress is relatively low.
In the course of the industrial use of melt spin finishes corresponding to German Pat. Nos. 26 45 459 and 26 45 890, it has turned out that such preparations may occasionally show cloudiness and possibly phase separation during use, especially when they remain for a longer periods of time in the vessels used for the finishing process. This cloudiness is observed especially with melt spin finishes containing alkoxylated fatty amines. Such alkoxylated fatty amines are frequently added to melt spin finishes in order to improve the frictional properties of the fibers and to reduce their static charge.